"Jake flipped out," a source from the movie said. "His character was looking into a mirror during the scene and punched the mirror in anger and broke it, cutting himself so bad he had to be taken to a hospital."

Another source told the celebrity magazine said Gyllenhaal has been "intensely focused" on his role as a crime-scene reporter in the movie. The source said that after receiving treatment for the injury, Gyllenhaal was cleared to return to the set.

"The scene was emotionally charged and his character was talking into a mirror and he got so into it, he banged his hands against the mirror and it broke and cut him," the source told People.com. "It was all the scene and not because he was mad about anything else."

"Nightcrawlers," which is expected to hit movie theaters next year, also stars Rene Russo and Bill Paxton. The story centers on a young, determined writer who discovers the underground world of Los Angeles freelance crime journalism.

"I can only approach things from a mental place," Gyllenhaal told E! News at the Hollywood Film Awards in October. "Like I'm playing a character who's hungry, figuratively and literally, who's driven in ways to do things and succeed at any cost. And I think that defines a generation in a lot of way so I wanted to get their mentally and then have it transform me physically, because I am not one to rely on science as much as I am on just sort of instinct. That's sort of the character."

Dan Gilroy, who co-wrote the "The Bourne Legacy," is directing the film and co-producing it with Gyllenhaal, Jennifer Fox, Michel Litvak and David Lancaster.